Craniofacial abnormalities frequently result in upper airway compromise and thus appear to be predisposing factors for the development of obstructive sleep apnea. However, no estimates of the prevalence of sleep apnea in the pediatric craniofacial clinic population have been reported. The objectives of this research are to estimate the prevalence of sleep apnea in this population and identify risk factors for diagnosis by polysomnography in a prospective observational cohort study of this population. A secondary objective is to validate the Pediatric Sleep Questionnaire (PSQ) as a screening tool in the craniofacial population. Long term objectives include validating sleep apnea quality of life outcome measures in this population and evaluating longitudinal natural history and treatment outcomes. Multivariate regression analysis will be used to quantify risk factors including age, race, symptoms, and craniofacial diagnosis. Criterion validity of the PSQ will be assessed by comparison with polysomnography results in a subset of the cohort. This study will allow better identification of children in the craniofacial clinic population who are most at risk for developing sleep apnea and inform the decision-making process for evaluation and treatment.